Add #[inline] to trivial functions on core::sync::Exclusive

[thomcc]

When optimizing for size things like these sometimes don't inlined even though they're generic. This is bad because they're no-ops.

Only dodgy one is poll I guess since it forwards to the inner poll, but it's not like we're doing #[inline(always)] here.

[rust-highfive]

r? @scottmcm

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[scottmcm]

Sure, this seems fine.

@bors r+ rollup=iffy

Only dodgy one is poll I guess since it forwards to the inner poll, but it's not like we're doing #[inline(always)] here.

Note that inlining is bottom-up, not top-down, so this encourages the whole thing to be inlined into the caller, including the inner poll if the inner poll was already inlined into it.

But if the inner poll is big it probably won't be, and then it makes sense again for this one to inline 🤷

[bors]

📌 Commit 29efe8c has been approved by scottmcm

It is now in the queue for this repository.

[thomcc]

Note that inlining is bottom-up, not top-down, so this encourages the whole thing to be inlined into the caller, including the inner poll if the inner poll was already inlined into it.

This is why I called it out as slightly dodgier than the others, but I don't think it will make a difference.

[bors]

⌛ Testing commit 29efe8c with merge cdb76db...

[bors]

☀️ Test successful - checks-actions
Approved by: scottmcm
Pushing cdb76db to master...

[rust-timer]

Finished benchmarking commit (cdb76db): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

Instruction count

This benchmark run did not return any relevant results for this metric.

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean1	range	count2
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-4.4%	[-4.4%, -4.4%]	1
All ❌✅ (primary)	-	-	0

Cycles

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean1	range	count2
Regressions ❌ (primary)	2.6%	[2.6%, 2.6%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	2.6%	[2.6%, 2.6%]	1

Footnotes

1. the arithmetic mean of the percent change ↩ ↩²

2. number of relevant changes ↩ ↩²

[therealprof]

Only dodgy one is poll I guess since it forwards to the inner poll, but it's not like we're doing #[inline(always)] here.

Why are we not doing #[inline(always)]? For true no-ops I don't see any need to be conservative here...